Unit filter assembly



Nov. 19, 1963 A. R. GETZIN UNIT FILTER ASSEMBLY Filed June 28, 1961INVENTOR. ALLAN R. GETZI N 3,111,439 UNIT FILTER ASSEMBLY Allan R.Getzin, .leli'ersontown, Ky., assignor to American Air Filter (Iornpany,line, Louisville, Ky, a corporation of Delaware Filed June 28, 1961,Ser. N 128,243 2 Claims. ($1. 210-232) The present invention relates toa filter assembly and more particularly to an improved filter assemblyarrangement which includes a unit filter medium supporting frame havingopen upstream and downstream faces to permit fluid flow through a filtermedium member which 1t supports.

In accordance with the present invention, a novel filter mediumsupporting frame is provided which can be economically and eificientlymass produced, which can be readily assembled for insertion and removalof the filter medium member which it supports and which can provideready liquid drainage whenever required.

Various other features of the present invention will become obvious toone skilled in the art upon reading the disclosure set forthhereinafter.

More particularly the present invention provides a unit filter assemblycomprising a pair of substantially identical filter frame halves, eachof the halves including a perirnetric base wall means and side wallmeans extending at right angles from the perimeter of the base wallmeans, spaced slot means in each of the side wall means to separate eachof the side wall means into even numbered first and second sets ofalternating side wall portions, with the side Wall portions within eachset being substantially equal in length to each other and with the sidewall portions of one set exceeding in length the side wall portions ofthe other set by at least substantially twice the side wall portionthickness of such other set whereby the frame halves can be interlockedwith side wall portions of the first set of one frame half facing theside Wall portions of the second set of the other frame half so as to bein fixed lateral position with respect to each other with each framehalf presenting at least one pair of side wall gripping portions forready Withdrawal and disconnect from the other frame half with which itis interlocked, the perimetric base wall means of the frame halvesdefining opposed openings to provide open upstream and downstream facesto permit fluid flow therethrough, and filter medium means disposedwithin the interlocked frame halves between the upstream and downstreamfaces.

It is to be understood that various changes can be made by one skilledin the art in the arrangement, form and construction of the apparatusdisclosed herein without departing from the scope or spirit of thepresent invention.

Referring to the drawing:

FIGURE 1 is an isometric view of a unit filter assembly whichincorporates features of the present invention;

FIGURE 2 is a reduced sectional view taken along line 22 of FIGURE 1;

FIGURE 3 is a reduced sectional view taken along line 3-3 of FIGURE 1;

FIGURE 4 is a plan view of a modified frame half of the presentinvention; and,

FIGURE 5 is a reduced perspective view, disclosing the ready manner ofassembly and disassembly of a unit filter arrangement incorporatingfeatures of the present invention.

As can be seen in FIGURES 1-3 of the drawing, the unit filter assemblyof the present invention broadly comprises an appropriately sized filtermedium member 1 interposed between a pair of interlocked filter framehalves 2, 2', which advantageously can be fabricated from BillfidfiPatented Nov. 1? i983 ree a suitable flexible material such as thingauge aluminum. The frame halves are identical in size and shape andthus are interchangeable to facilitate mass production and assembly.Although, advantageously, the frame halves disclosed are of four sidedshape and of hand size, it is to be understood that the presentinvention is not limited to this particular size and shape frame butthat other sizes and other shapes which include side wall portions ofeven number can be utilized.

Frame halves 2, Z in the embodiment of the invention set forth hereineach includes a perimetric, rectangularly shaped base wall 3, 3,respectively, with each base wall 3 and 3 having two sets of side wallportions 4, 5 and 4', 5, respectively, all of substantially uniformthickness, extending at right angles from the outer perimeters thereof.It is to be noted that there are an even number of side wall portions ineach side wall set with the side wall portions of sets 4 and 4'alternating with side wall portions of sets 5 and 5', respectively andwith corner slots 6, 6 serving to separate adjacent side wall portionsin frame halves 2 and 2, respectively. It further is to be noted thatthe length of the side wall portions of sets t and 4 exceed the lengthof the side wall portions of sets 5 and 5', respectively, by a distanceof approximately twice the side wall portions thickness. With such anarrangement, it is possible to interlock frame halves 2, 2' in such amanner that they cannot be shifted laterally with respect to each other,i.e., in a plane parallel to the planes of base walls 3, 3. Thisinterlocking can be accomplished by orienting the frame halves 2, 2'with respect to each other so that side wall portions of sets 4 and 4'in each frame half respectively face the side wall portions of sets 5and 5' in the respectively opposite frame half. Since the side wallportions of sets 4 and 4' are of greater length than the side wallportions of sets 5 and S, the side wall portions of sets 5 and 5' inframe halves 2 and 2, respectively, fall along the outside faces of theside wall portions of sets 4 and 4, respectively, to provide a pair ofopposed gripping surfaces available on each frame half.

To provide open upstream and downstream faces to permit fluid flowtherethrough, perimetric base walls 3, 3' of frame halves 2, 2 eachdefine an opposed opening '7, 7, respectively. Prior to assembly offilter frame halves 2, 2', a suitable filter medium member 1 can beinserted between the frame halves. It is to be understood that thisfilter medium, which can be any one of a number of well known filtermediums (i.e., fiber glass), is sized to nest in snug engagement betweenframe halves. Suitable filter medium retaining members 11, whichadvantageously can be of expanded metal or perforated hardware cloth,are also sized to correspond with the filter frame halves and can beinserted between the frame halves along either face of the filter mediummember 1 to further retain the filter medium member 1 in the assembledframe.

It is to be noted that the aforedescribed corner slots 6, 6' allowflexing of the side wall portions whenever necessary for close facing ofthe side wall portions upon frame halves interlocking and, in addition,these slots can be dimensioned to serve effectively as drainage meansfor any excess liquids which might be on or collect upon filter mediummember 1. It further is to be noted that there can be provided in placeof separate filter medium retaining members 11, as disclosed in FIGURES1-3 of the drawing, suitable filter medium retaining grid structure 12integral with each frame half in order to reduce the cost of manufactureand to further increase the efiiciency of filter unit assembly anddisassembly (FIGURE 4).

Referring to FIGURE 5 of the drawing, it can be seen that a smallrectangular hand size unit which incorporates the features of thepresent invention can be readily assembled and disassembled Without useof any tools whatsoever. In assembly, it only is necessary to hold aframe half of the present invention in each hand and, with anappropriately sized filter medium member disposed therebetween, theframe halves in each hand can be brought into interlocking engagementwith each other so that the shorter side wall portions of each framehalf face against the outer faces of the longer side wall portions ofthe other frame half. With this interlocking arrangement, the outershort side wall portions of the frame halves serve as ready grippingsurfaces when the interlocked frame halves are to be pulled apart forinsertion of a fresh filter medium member therebetween.

The invention claimed is:

l. A unit filter assembly comprising a pair of substantially identicalfilter frame halves, each of said halves including a perimetric baseWall means and side wall means extending at right angles from theperimeter of said base wall means, spaced slot means in each of saidside wall means to separate each of said side wall means into evennumbered first and second sets of alternating side wall portions withthe side wall portions within each set being substantially equal inlength to each other and with the side wall portions of one setexceeding in length the side wall portions of the other set byapproximately twice the side wall portion thickness of such other setwhereby said frame halves can be interlocked with side wall portions ofthe first set of one frame half facing the side Wall portions of thesecond set of the other frame half so as to be in fixed lateral positionwith respect to each other with each frame half presenting at least onepair of side wall gripping portions for ready withdrawal and disconnectfrom the other frame half means of said frame halves defining opposedopenings to provide open upstream and downstream faces to permit fluidflow therethrough, and filter medium means disposed within saidinterlocked frame halves between said upstream and downstream faces.

2. A unit filter assembly comprising a pair of substantially identicalfilter frame halves, each of said halves including a rectangularperimetric base wall and a rectangular side wall extending at rightangles from the perimeter of said base wall, spaced corner slots in eachof said side walls to separate each of said side walls into first andsecond sets of opposed side wall portions with the opposed side Wallportions of each set being substantially equal to each other in lengthand with the side wall portions of one set exceeding in length the sideWall portions of the other set by approximately twice the side wallportion thickness of such other set whereby said frame halves can beinterlocked withside wall portions of the first set of one frame halffacing the side wall portions of the second set of the other frame halfso as to be in fixed lateral position with respect to each other witheach frame half presenting a pair of opposed side wall gripping portionsfor ready withdrawal and disconnect from the other frame half with whichit is interlocked, said perimetric base wall of said frame halvesdefining opposed openings to provide open upstream and downstream facesto permit fluid flow therethrough, and filter medium means disposedwithin said interlocked frame halves between said upstream anddownstream faces.

Slayter et al May 30, 1939 Hunsworth Jan. 1, 1952

1. A UNIT FILTER ASSEMBLY COMPRISING A PAIR OF SUBSTANTIALLY IDENTICALFILTER FRAME HALVES, EACH OF SAID HAVES INCLUDING A PERIMETRIC BASE WALLMEANS AND SIDE WALL MEANS EXTENDING AT RIGHT ANGLES FROM THE PERIMETEROF SAID BASE WALL MEANS, SPACED SLOT MEANS IN EACH OF SAID SIDE WALLMEANS TO SEPARATE EACH SIDE WALL MEANS INTO EVEN NUMBERED FIRST ANDSECOND SETS OF ALTERNATING SIDE WALL PORTIONS WITH THE SIDE WALLPORTIONS WITHIN EACH SET BEING SUBSTANTIALLY EQUAL IN LENGTH TO EACHOTHER AND WITH THE SIDE WALL PORTIONS OF ONE SET EXCEEDING IN LENGTH THESIDE WALL PORTIONS OF THE OTHER SET BY APPROXIMATELY TWICE THE SIDE WALLPORTION THICKNESS OF SUCH OTHER SET WHEREBY SAID FRAME HALVES CAN BEINTERLOCKED WITH SIDE WALL PORTIONS OF THE FIRST SET OF ONE FRAME HALFFACING THE SIDE WALL PORTIONS OF THE SECOND SET OF THE OTHER FRAME HALFSO AS TO BE IN FIXED LATERAL POSITION WITH RESPECT TO EACH OTHER WITHEACH FRAME HALF PRESENTING AT LEAST ONE PAIR OF SIDE WALL GRIPPINGPORTIONS FOR READY WITHDRAWAL AND DISCONNECT FROM THE OTHER FRAME HALFWITH WHICH IT IS INTERLOCKED, SAID PERIMETRIC BASE WALL MEANS OF SAIDFRAME HALVES DEFINING OPPOSED OPENINGS TO PROVIDE OPEN UPSTREAM ANDDOWNSTREAM FACES TO PERMIT FLUID FLOW THERETHROUGH, AND FILTER MEDIUMMEANS DISPOSED WITHIN SAID INTERLOCKED FRAME HALVES BETWEEN SAIDUPSTREAM AND DOWNSTREAM FACES.